I need to invest in an external HD for my MacBook (which has a 100Gb drive). The main purpose at this point is for backups (i.e. I want to have a bootable backup drive). At this time I don't have a digital video camera, or a large music collection, or any of the typical things that tend to consume hard drive space. This drive (a 120Gb Seagate, price $62.99 plus shipping) looks like a winner for my purposes. My primary concern is this: Should I be looking for a larger capacity drive (e.g. this model, a 320Gb drive)? P.S. Probably going to pair it with this enclosure (the MacAlly FW400+USB combo). If you have an opinion about that choice, I'd like to hear it as well.